Airfoil with trailing edge rounding

Abstract

An airfoil for a gas turbine engine includes a substrate portion extending from an airfoil leading edge to an airfoil trailing edge portion. The airfoil trailing edge portion includes a flared portion wherein a substrate portion thickness increases along a camber line of the airfoil, and a trailing edge defined as a full constant radius extending from a pressure side of the airfoil to a suction side of the airfoil. A coating portion includes a coating applied over at least a portion of the substrate portion.

What is claimed is: 
     
       1. An airfoil for a gas turbine engine, comprising:
 a substrate portion extending from an airfoil leading edge to an airfoil trailing edge portion, the airfoil trailing edge portion including:
 a flared portion wherein a substrate portion thickness increases along a camber line of the airfoil with increasing distance from the airfoil leading edge; and 
 a trailing edge located downstream of the flared portion, extending from a pressure side of the airfoil to a suction side of the airfoil; and 
 
 a coating portion comprising a coating applied over at least a portion of the substrate portion, the coating portion having a coating trailing surface and a coating outer surface, the coating trailing surface and the coating outer surface defining a coating trailing edge at an intersection thereof spaced from the substrate portion in a thickness direction and spaced upstream from a maximum thickness location of the flared portion in a camberwise direction. 
 
     
     
       2. The airfoil of  claim 1 , wherein the coating portion includes:
 a body portion having a substantially constant coating thickness; and 
 a taper portion disposed between the body portion and the coating trailing surface. 
 
     
     
       3. The airfoil of  claim 2 , wherein the taper portion extends to the coating trailing surface. 
     
     
       4. The airfoil of  claim 1 , wherein the substrate portion is formed by casting. 
     
     
       5. The airfoil of  claim 1 , wherein the trailing edge is formed by one or more machining processes. 
     
     
       6. The airfoil of  claim 1 , wherein the coating is a thermal barrier coating. 
     
     
       7. The airfoil of  claim 1 , further comprising a core center discharge at the trailing edge to exhaust a cooling airflow from an interior of the airfoil. 
     
     
       8. A method of forming an airfoil for a gas turbine engine, comprising:
 forming an airfoil substrate portion, the airfoil substrate portion including an airfoil leading edge and an excess material portion at a trailing edge region of the airfoil substrate portion; and 
 machining the excess material portion to define:
 a flared portion wherein a thickness of the substrate portion increases along a camber line of the airfoil with increasing distance from the airfoil leading edge; and 
 a trailing edge located downstream of the flared portion, the trailing edge defined as a selected shape extending from a pressure side of the airfoil to a suction side of the airfoil; 
 
 applying a coating portion comprising a coating over at least a portion of the substrate portion, the coating portion having a coating trailing surface and a coating outer surface, the coating trailing surface and the coating outer surface defining a coating trailing edge at an intersection thereof spaced from the substrate portion in a thickness direction and spaced upstream from a maximum thickness location of the flared portion in a camberwise direction. 
 
     
     
       9. The method of  claim 8 , wherein the machining the excess material portion to define the selected shape comprises forming a full constant radius extending from the pressure side to the suction side. 
     
     
       10. The method of  claim 8 , wherein applying the coating portion comprises:
 applying a body portion having a substantially constant coating thickness; and 
 applying a taper portion disposed between the body portion and the coating trailing surface. 
 
     
     
       11. The method of  claim 10 , wherein the taper portion extends to the coating trailing surface. 
     
     
       12. The method of  claim 8 , wherein the coating is a thermal barrier coating.